1. Field of the Invention
This invention relates to a valve moving push rod for internal combustion engines obtained by improving the fusing strength of an end piece and to a method of making the same.
2. Description of the Prior Art
A conventional push rod of this kind is obtained solely by welding by an electric resistance welding method an end piece having the end surface formed to be a concave or convex arcuate surface and having a carbon-hardened layer formed on the peripheral wall surface to the peripheral edge of a port at one or each end of a steel tube material. The arts as above described have been proposed by, for example, U.S. Pat. No. 2,975,775 and No. 2,960,080. However, according to these prior arts, the end piece accidentally drops sometimes during the operation of the engine.